1. Field of the Invention
The present invention relates to a telescopic tube set for a bridge transport system, and more particularly to a telescopic tube set for a bridge transport system capable of
2. Description of the Related Art
A bridge transport system is used to move remote handling equipment such as a servo manipulator and tools to an interior of a hot cell.
Such a bridge transport system may include main modules to move in x, y and z-directions in a hot cell, which include a girder, a trolley and a telescopic tube set, and auxiliary modules including a power and signal cable management system, remote handling equipment, a tool attachment die, hoist crane, etc.
An example of a telescopic tube moving device, which is included in the bridge transport system configured as mentioned above, is shown in FIG. 1.
As shown in FIG. 1, the telescopic tube moving device, which moves a telescopic tube set 100, includes a girder 300, a trolley 200, and a guide rail 400. The telescopic tube set 100 functions to vertically move a servo manipulator, etc., and includes a plurality of tubes having different diameters.
As shown in FIG. 1, each tube of the telescopic tube set basically has a square cross-section. A linear motion (LM) guide rail and a block are installed at one side wall surface of each tube, to uniformly guide extension and retraction of the tube.
The remaining wall surfaces of each tube, except for the wall surface, at which the LM guide and block are installed, are formed by thin covers. In this telescopic tube set, there is an advantage in that high motion accuracy and high reliability are achieved by the provision of the LM guide. However, there may be a problem of eccentricity because only the wall of each tube where the LM guide is installed is thick, whereas the remaining walls of the tube are thin, so that the center of gravity of the tube is biased to one side of the tube.
Furthermore, there may be a structural problem of poor resistance to bending and torsion because only the wall of each tube where the LM guide is installed is thick, whereas the remaining walls of the tube are thin.
Although not shown, the telescopic tube set, which includes a plurality of tubes, as mentioned above, uses a device for extending or retracting each tube of the telescopic tube set. However, the extension/retraction device is installed outside the telescopic tube set. For this reason, the extension/retraction device may be contaminated by dust, etc., so that it may malfunction upon extension or retraction of the telescopic tube set. In addition, the user or other devices may bump into the extension/retraction device, possibly resulting in injury or damage.
Moreover, such a conventional telescopic tube has a problem in that it is difficult to achieve accurate control because the extension and retraction of the telescopic tube are carried out, starting from the outermost tube and innermost tube, respectively.